(DoS) Attacks | The Basics

(DoS) attack is kind of attack in which an attacker or intruder tries to deprive system users or authorized users from accessing remote computer, network or a site. An attacker usually targets bandwidth of victim to perform this attack.
Illegal use of internal resources may also result in denial of service hence it is not always the case that system has been attacked remotely it can be attacked from internal network from an unsatisfied or disgruntled employee. It can also be executed against network resources, services and data access in a networked environment. In all motive of denial of service is only destruction not stealing.

As a typical result of DoS a system may hang, respond slowly, reboot or shutdown a system. A worst case result may include loss of information, damage of network resources and hardware and ultimately deletion, destruction of data and programs of users that were online during attack. Thus DoS attack compromises system without intruding and is enough to disorganize organized infrastructure and functionality of an organization.

A denial of service attack is called distributed denial of service (DDoS) attack when DoS attack is performed using several devices. In older times these devices were only computer but today’s scope is much bigger than only computers.

Now depending on what factor attacker has planned to attack modes of attacks are classified as follows,

1.Attack Against Connectivity:

In this kind of attack an attacker tries to stop hosts or users from connecting and communicating with another host or computer.

2.Misuse Of Internal Resources:

In this mode of attack an attacker tries to bind resources to specific machines which results in consumption network bandwidth and wastage and non-availability of resources for others.

3.Bandwidth Consumption:

In this mode of attack attacker generates large number of packets from system on which attack has been planned to be performed. Resulting consumption of bandwidth finally lead its unavailability for others and results in DoS attack.

4.Consumption Of Network Resources:

In this mode of attack an attacker tries to consume resources on network.

5.Altering Configuration:

In this attack mode an attacker may try to exploit misconfigured information present on network for DoS.

Depending upon selected mode of attack DOS attacks are classified as,

SYN Attack

Smurf DoS

Buffer Overflow

Ping of Death

Tear Drop

But lets leave it for future discussion, I hope I kept it damn easy to understand if you have any problem understanding anything above, please don’t hesitate to ask. Thanks for reading, keep visiting.